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Water’s molar mass is 18.01 g/mol. The molar mass of glycerol is 92.09 g/mol. At 25°C, glycerol is more viscous than water. Which substance has the stronger intermolecular attraction?

A
glycerol because it has a larger molar mass
B
glycerol because it is more viscous and has a larger molar mass
C
water because it has a lower molar mass
D
water because it is less viscous and has a lower molar mass
2
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This heating curve is produced when a certain substance is heated.Which best compares the particles of the substance when it is in region 1 with the particles of the substance when it is in region 3?

Question illustration
A
The particles are slower in region 3.
B
The particles are more orderly in region 1.
C
The particles have more kinetic energy in region 1.
D
The particles have less freedom of motion in region 3.
3

How many kPa are in 2,150 mmHg?

A
2.83 kPa
B
287 kPa
C
1.61 ´ 104 kPa
D
2.18 ´ 105 kPa
4

Which is an aspect of the kinetic-molecular theory and can be used to explain the behavior of plasmas?

A
Particle spacing can allow a very high density.
B
Particle kinetic energy is independent of temperature.
C
Particles vibrate quickly in stationary positions.
D
Particles exchange energy through elastic collisions.
5

Considering the temperature vs. time graph below, how does the temperature at the beginning of a change of state compare with the temperature at the end of the change?

Question illustration
A
The temperature is always lower.
B
The temperature is always the same.
C
The temperature is usually lower.
D
The temperature is usually higher.
6

A substance is tested in a lab. It is found to maintain a unique shape and is a good conductor of electricity. If it is made up of electrons, protons, and neutrons, what state of matter is this substance most likely to be?

A
gas
B
liquid
C
plasma
D
solid
7

The particles of a gas inside a balloon are experiencing an increase in their average kinetic energy and the number of collisions with the wall of the balloon. What is the most likely outcome?

A
higher gas pressure inside the balloon
B
higher air pressure outside the balloon
C
a decrease in gas temperature inside the balloon
D
a large increase in air temperature outside the balloon
8

Which best defines partial pressure in a mixture of gases?

A
pressure that is exerted by all the gases of a mixture on the container
B
pressure that is exerted by one gas as if it occupied a container by itself
C
half of the pressure that is exerted by the gases of a mixture on the container
D
sum of the individual pressures that are exerted by two or more gases
9

According to the kinetic-molecular theory, the average kinetic energy of gas particles depends on which factor?

A
volume
B
pressure
C
temperature
D
number of particles
10

Which statement best explains why heating a liquid affects its viscosity?

A
The molecules move faster at higher temperatures and overcome attractions more easily.
B
The molecules move faster at higher temperatures, and the attractions between them increase.
C
The molecules move slower at higher temperatures and overcome attractions more easily.
D
The molecules move slower at higher temperatures, and the attractions between them decrease.
11

The incomplete table below shows a comparison of the different gas laws.NameVariablesConstantsEquationBoyle's law pressure, volume? Charles’s lawvolume, temperature??temperature, pressurevolume, moles of gas?pressure, temperature, volume?What is assumed to be constant when using the combined gas law?

Question illustration
A
pressure
B
number of moles
C
volume and moles of gas
D
pressure and temperature
12

Which best defines pressure?

A
a measure of the number of particles in a unit area
B
a measure of the force of the collision of particles on a unit area
C
a measure of the number of particles on the outside of a container
D
a measure of the force of the collision of particles on the inside of a container
13

Which describes the volume of 1 mol of gas at standard temperature and pressure?

A
The volume is greater for a larger mass of gas.
B
The volume is the same for any gas.
C
The volume depends on the size of the container.
D
The volume varies with the pressure.
14

If the pressure, volume, and temperature of a gas are known, which can most likely be found by using the ideal gas law?

A
the molar amount of the gas
B
the partial pressure of the gas
C
the standard temperature and pressure
D
the molar mass
15

Which of the following best identifies where long-range order would be found?

A
in amorphous solids
B
in crystalline solids
C
in thermal plasmas
D
in nonthermal plasmas
16

Which change of state involves a release of energy?

A
boiling
B
condensation
C
melting
D
sublimation
17

The volume of a gas is 0.450 L when its pressure is 1.00 atm. If the temperature of the gas does not change, what is the pressure when its volume is changed to 2.00 L?Use .

Question illustration
A
0.225 atm
B
0.444 atm
C
2.25 atm
D
4.44 atm
18

The gas in the piston is at constant temperature. A student increases the pressure on the piston from 2 atm to 3 atm.Which gas law would a student use to investigate this situation?

Question illustration
A
Boyle’s law
B
Charles’s law
C
Gay-Lussac’s law
D
ideal gas law
19

Which device involves the use of plasma in technology?

A
arc welder
B
diesel engine
C
a car radio
D
battery-operated flashlight
20

The diagram below shows the different phase transitions that occur in matter. Which arrow represents the transition in which dew is formed?

Question illustration
A
1
B
2
C
4
D
6

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